The present disclosure relates to a solid-state imaging device and a manufacturing method thereof, and an electronic apparatus such as a camera having the solid-state imaging device.
There is a CCD solid-state imaging device or a CMOS solid-state imaging device as a solid-state imaging device (image sensor). The solid-state imaging device is used for digital still cameras, digital video cameras, and various portable terminal apparatuses such as mobile phones with cameras.
In recent years, a rear surface irradiation type CMOS solid-state imaging device has been used as a solid-state imaging device for improving sensitivity. FIG. 28 shows an example of main parts of the rear surface irradiation type CMOS solid-state imaging device. The rear surface irradiation type CMOS solid-state imaging device 1 is provided with a thinned semiconductor substrate 2 where photodiodes PD which are a photoelectric conversion unit are formed from the front surface to the rear surface and a plurality of pixel transistors forming pixels are formed on the front surface side. In the figure, each of the plurality of pixel transistors is represented by a transmission transistor Tr1 having a transmission gate electrode 3. A multi-layer wire layer 6 where a plurality of wires 5 are disposed is formed on the front surface of the semiconductor substrate 2 via an interlayer insulating layer 4, and a supporting substrate 8 is joined to the multi-layer wire layer 6 via an adhesive layer 7. A planarization film 10 is formed on the rear surface of the semiconductor substrate 2 via an insulating layer 9 formed of a plurality of layers, and on-chip color filters (hereinafter, referred to as color filters) 11 and on-chip micro lenses (hereinafter, referred to as micro lenses) 12 are formed on the planarization film 10.
On the other hand, Japanese Unexamined Patent Application Publication No. 9-8261 discloses a solid-state imaging device where a passivation film and a transparent dielectric film having a refractive index higher than the passivation film formed thereon are formed in a light incident opening surrounded by light blocking layers at the upper side of photodiodes. The passivation film is made of a NSG film, a PSG film, or the like, and the transparent dielectric film is made of an acrylate resin. In this solid-state imaging device, light incident to the passivation film can be collected at the photodiodes.
In order to improve light collecting efficiency at a photodiode, solid-state imaging devices with a waveguide structure built therein are disclosed in Japanese Unexamined Patent Application Publication No. 7-45805 and Japanese Patent No. 4165077.